Calculating machines do sums better than even the cleverest people… As arithmetic has grown easier, it has come to be less respected.

Ever since men became capable of free speculation, their actions, in innumerable important respects, have depended upon their theories as to the world and human life, as to what is good and what is evil. This is true in the present day as at any former time. To understand an age or a nation, we must understand its philosophy, and to understand its philosophy we must ourselves be in some degree philosophers. There is here a reciprocal causation: the circumstances of men s lives do much to determine their philosophy, but, conversely, their philosophy does much to determine their circumstances.

When anaesthetics were invented they were thought to be wicked as being an attempt to thwart God's will. Insanity was thought to be due to diabolic possession, and it was believed that demons inhabiting a madman could be driven out by inflicting pain upon him, and so making them uncomfortable. In pursuit of this opinion, lunatics were treated for years on end with systematic and conscientious brutality.

Science, by itself, cannot supply us with an ethic. It can show us how to achieve a given end, and it may show us that some ends cannot be achieved.

Ordinary language is totally unsuited for expressing what physics really asserts, since the words of everyday life are not sufficiently abstract. Only mathematics and mathematical logic can say as little as the physicist means to say.

Real life is, to most men, a long second best, a perpetual compromise between the ideal and the possible.

One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision.